K-Beauty Glossary
What is Occlusive?
Barrier that seals moisture in
Occlusives form a film on the skin surface that dramatically reduces transepidermal water loss. They don't hydrate — they seal in what's underneath. The gold standard is petrolatum (Vaseline), which reduces TEWL by 99%. Other classics: lanolin, dimethicone, beeswax, shea butter. Applying an occlusive as the final step of a nighttime routine in dry weather is the Korean beauty 'slugging' technique.